In an effort to eludicate the parameters that govern hemocampatibility; the influence of molecular motion in polymers with long side chains on the initial adsorption of the blood plasma proteins and subsequent thrombogenesis will be studied. The degree and type of side chain and segmental molecular backbone motion in poly (gamma-benzyl-L-glutamate), block copolymers thereof, and other polymers will be determined by dynamic and conventional mechanical spectroscopy, as a function of side chain crosslinking, morphology, and temperature. The specific amounts of adsorption (and any associated conformational changes) of albumin, fibrinogen/fibrin, polypeptides of given hydrophobicity, and Factors VII, IX and X onto these defined polymeric surfaces will be documented by total internal reflectance fluorescence spectroscopy and microcalorimetry. The temperol pattern for the preferential adsorption of the blood plasma proteins and cells onto these graded polymeric surfaces will be obtained by placing them in an extracorporeal shunt and by using radio-isotope labelled proteins and cells. The results of the in vitro and ex vivo studies will be compared in order to ascertain the major parameters that govern the initial adsorption of the plasma proteins and how this layer ultimately affects the cellular response through the mediation of this deposited protein layer.